US5039116A - Composite oil-ring - Google Patents
Composite oil-ring Download PDFInfo
- Publication number
- US5039116A US5039116A US07/520,118 US52011890A US5039116A US 5039116 A US5039116 A US 5039116A US 52011890 A US52011890 A US 52011890A US 5039116 A US5039116 A US 5039116A
- Authority
- US
- United States
- Prior art keywords
- ring
- oil
- seal ring
- spring
- groove
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
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Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16J—PISTONS; CYLINDERS; SEALINGS
- F16J9/00—Piston-rings, e.g. non-metallic piston-rings, seats therefor; Ring sealings of similar construction
- F16J9/12—Details
- F16J9/20—Rings with special cross-section; Oil-scraping rings
- F16J9/206—One-piece oil-scraping rings
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16J—PISTONS; CYLINDERS; SEALINGS
- F16J9/00—Piston-rings, e.g. non-metallic piston-rings, seats therefor; Ring sealings of similar construction
- F16J9/06—Piston-rings, e.g. non-metallic piston-rings, seats therefor; Ring sealings of similar construction using separate springs or elastic elements expanding the rings; Springs therefor ; Expansion by wedging
- F16J9/064—Rings with a flat annular side rail
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16J—PISTONS; CYLINDERS; SEALINGS
- F16J9/00—Piston-rings, e.g. non-metallic piston-rings, seats therefor; Ring sealings of similar construction
- F16J9/06—Piston-rings, e.g. non-metallic piston-rings, seats therefor; Ring sealings of similar construction using separate springs or elastic elements expanding the rings; Springs therefor ; Expansion by wedging
- F16J9/064—Rings with a flat annular side rail
- F16J9/066—Spring expander from sheet metal
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16J—PISTONS; CYLINDERS; SEALINGS
- F16J9/00—Piston-rings, e.g. non-metallic piston-rings, seats therefor; Ring sealings of similar construction
- F16J9/12—Details
- F16J9/20—Rings with special cross-section; Oil-scraping rings
- F16J9/203—Oil-scraping rings
Definitions
- the present invention relates to an oil-ring for disposition in an oil-ring groove of a piston of an internal combustion engine. More specifically, the invention relates to a composite oil-ring consisting of three ring pieces.
- oil-rings of different types have been known for use with a piston of an internal combustion engine.
- Conventional oil-rings can be roughly classified by the following two types.
- One is a so-called solid oil-ring and the other is a three-piece type oil-ring.
- a solid oil-ring is constructed of, mainly, one ring piece which has an expansion force in its radial direction by itself and slidably contacts a cylinder bore.
- a three-piece type oil-ring is constructed of a pair of side rails and an expander disposed between the side rails and urging the side rails both radially toward a cylinder bore and axially toward the upper or lower surface of an oil-ring groove.
- a solid oil-ring usually does not exert a force for sealing between the oil-ring and the upper or lower surface of an oil-ring groove, because one oil-ring is merely disposed in the oil-ring groove and thereafter inserted in a cylinder bore. Moreover, since the solid oil-ring itself has abutted end portions on its circumference, a gap between the abutted end portions forms an oil and gas path in a vertical direction, i.e. a direction along an axis of a cylinder bore.
- Japanese Utility Model Publication SHO 48-13288 discloses an oil-ring structure designed to increase the axial sealing force of a solid type oil-ring, thereby reducing oil consumption in an internal combustion engine, as shown in FIG. 8.
- oil-ring 1 installed in oil-ring groove 2 of piston 3 consists of solid ring 4 and spring ring 5 having a belleville spring structure, which slidably contacts cylinder bore 6. Solid ring 4 is pressed onto the upper surface 2a of oil-ring groove 2 by the spring force of spring ring 5.
- An object of the present invention is to provide a composite oil-ring including a solid type oil control ring, which can substantially prevent the formation of an axial oil path past an oil-ring portion, and can decrease oil loss to a great extent, thereby greatly decreasing oil consumption.
- the composite oil-ring according to the present invention satisfies the above object and is intended to be disposed in an oil-ring groove formed in a piston which is inserted to move reciprocally in a cylinder bore to constitute a piston and cylinder sealing assembly.
- the composite oil-ring according to the present invention comprises an oil control ring disposed on a lower surface of the oil-ring groove, an outer surface of the oil control ring in a radial direction of the oil control ring slidably contacting the cylinder bore; a seal ring disposed on an upper surface of the oil control ring, an outer surface of the seal ring in a radial direction of the seal ring slidably contacting the cylinder bore, the seal ring having abutted end portions which are formed a stepped portions engaging each other in the radial direction of the seal ring and substantially having no oil path in the radial direction of the seal ring; and a spring seal ring disposed between an upper surface of the seal ring and an upper surface of the oil-ring groove
- the oil control ring scrapes the oil on the cylinder bore, and most of the scraped oil is returned downwards and a part of the rest of the scraped oil enters into the interior of the oil-ring groove through a gap between the abutted end portions of the oil control ring.
- the seal ring functions as an auxiliary ring for scraping the oil on the cylinder bore.
- the spring seal ring Since the clearance in the radial direction are formed on both sides of the inner and outer surfaces, respectively, of the spring seal ring, it becomes possible to set the abutment gap of the ends of the spring seal ring substantially to zero.
- the spring seal ring functions as a belleville spring exerting a spring force in the axial direction.
- a part of the upper surface of the spring seal ring presses against the upper surface of the oil-ring groove along the whole circumference of the spring seal ring, and a part of the lower surface of the spring seal ring presses against the upper surface of the seal ring, so that the oil control ring is pressed onto the lower surface of the oil-ring groove via the seal ring.
- the seal ring substantially does not have an oil path in the radial direction and the abutment gap between the ends of the spring seal ring is zero, the oil that has entered into the interior of the oil-ring groove cannot escape in the radially outer direction through the abutted end portions of the seal ring and the spring seal ring. Therefore, the oil loss due to the escape of oil in this direction becomes substantially zero.
- the amount of the escaping oil upward through the composite oil-ring can be suppressed to an extremely small amount, oil loss can be decreased, and oil consumption can be decreased to a great extent.
- FIG. 1 is a vertical sectional view of a composite oil-ring and its vicinity according to an embodiment of the present invention
- FIG. 2 is a partial elevational view of the composite oil-ring and its vicinity shown in FIG. 1;
- FIG. 3 is an entire plan view of an oil control ring of the composite oil-ring shown in FIG. 1;
- FIG. 4 is an entire plan view of a seal ring of the composite oil-ring shown in FIG. 1;
- FIG. 5 is an entire plan view of a spring seal ring in its free stat of the composite oil-ring shown in FIG. 1;
- FIGS. 6A and 6B are vertical sectional views of oil control rings according to other embodiments of the present invention.
- FIG. 7 is a partial elevational view of an oil control ring according to a further embodiment of the present invention.
- FIG. 8 is a vertical sectional view of a conventional oil-ring and its vicinity.
- FIGS. 1-5 illustrate a composite oil-ring according to an embodiment of the present invention.
- a composite oil-ring 11 is disposed in an oil-ring groove 12 formed in a piston 13 which is reciprocally positioned in a cylinder bore 14 of an internal combustion engine.
- Composite oil-ring 11 consists of three ring pieces, namely, an oil control ring 15, a seal ring 16 and a spring seal ring 17.
- Oil control ring 15 is disposed on a lower surface 12a of oil-ring groove 12. A radially outer surface 15a of oil control ring 15 slidably contacts cylinder bore 14. As shown in FIG. 3, oil control ring 15 is constructed of an annular strip having abutted end portions 18a, 18a on its circumference. Abutted end portions 18a, 18a comprise a pair of flat end surfaces facing each other across a gap 18.
- abutted end portions 31a and 31b provided on an oil control ring 32 are formed as stepped portions engaging each other in the axial direction of the oil control ring and with a gap 31 in the circumferential direction.
- Radially outer surface 15a of oil control ring 15 is formed with a downwardly outward taper, such that only the bottom portion of the outer surface slidably contacts the cylinder bore.
- the outer surface may be formed in other shapes.
- an outer surface 41a of an oil control ring 41 has a convex cross section, so that only an axially central portion of the outer surface of the oil control ring will contact a cylinder bore.
- an outer surface 42a of an oil control ring 42 is formed as a cylindrical surface, substantially the whole of which can contact a cylinder bore.
- Seal ring 16 is disposed on an upper surface 15b of oil control ring 15. A radially outer surface 16a of seal ring 16 slidably contacts cylinder bore 14. As shown in FIG. 4, seal ring 16 is constructed of an annular strip having stepped end portions 19a and 19b abutting with a circumferential gap 19, but engaging each other in the radial direction of seal ring 16. Thus, even when the seal ring expands in the circumferential direction, the abutted end portions do not provide an oil path in the radial direction. Therefore, seal ring 16 substantially has no oil path in the radial direction of the ring.
- An abrasion-resistant material 20 for example, a hard chrome plating layer, is coated on at least one of, and preferably both outer surfaces 15a and 16a of oil control ring 15 and seal ring 16, in order to increase abrasion resistance thereof.
- Spring seal ring 17 is disposed between an upper surface 16b of seal ring 16 and an upper surface 12b of oil-ring groove 12.
- the inner and outer diameters of spring seal ring 17 are selected so as to define a radial clearance between an inner circumferential surface 17c of the ring and radially opposed circumferential surface of the assembly such as surface 12c of oil-ring groove 12 and a radial clearance between an outer circumferential surface 17a of the ring and a radially opposed circumferential surface of the assembly such as cylinder bore 14 when the ring is installed in the oil-ring groove.
- a groove 21 is formed on circumferential surface 12c of oil-ring groove 12 for creating the above radial clearance between inner surface 17c of spring seal ring 17 and the circumferential surface of the oil-ring groove. If this radial clearance can be formed without groove 21, the groove is not necessary.
- Spring seal ring 17 is constructed of an annular strip as shown in FIG. 5 and is constituted as a belleville spring structure.
- FIG. 5 illustrates spring seal ring 17 in its free state. In the free state, the end portions 22a and 22b of the annular strip overlap each other. Spring seal ring 17 is expanded from the above free state, and thereafter inserted in oil-ring groove 12 so that end portions 22a and 22b abut each other with no gap in the circumferential direction, as shown in FIG. 2. Therefore, the abutment gap 22 in the circumferential direction at abutted end portions of spring seal ring 17 is substantially zero when the ring is installed in oil-ring groove 12.
- spring seal ring 17 is constituted as a belleville spring structure having a spring force acting in an axial direction of the ring.
- a part of an upper surface 17b of spring seal ring 17 presses against upper surface 12b of oil-ring groove 12, and a part of a lower surface 17d of the spring seal ring presses against upper surface 16b of seal ring 16 and thus presses oil control ring 15 onto lower surface 12a of oil-ring groove 12 via the seal ring.
- the outer diameter of spring seal ring 17 when it is installed in oil-ring groove 12 is selected to be smaller than the diameter of piston 13 at a position of a land portion 23 thereof (see FIG. 1). In this way, outer surface 17a of spring seal ring 17 is prevented from directly contacting cylinder bore 14 even when piston 13 slaps.
- each of the oil return paths communicates between lower surface 12a and circumferential surface 12c of oil-ring groove 12 and also with the interior (not shown) of piston 13.
- the oil on cylinder bore 13 is scraped downwards mainly by the bottom portion of outer surface 15a of oil control ring 15, and a part of the remaining oil on the cylinder bore is scraped downwards by outer surface 16a of seal ring 16. Therefore, composite oil-ring 11 can scrape the oil much more efficiently than the conventional oil-ring constructed of merely one solid ring.
- oil control ring 15 and seal ring 16 can randomly rotate independently, it is stochastically a rare case that circumferential gap 18 of the oil control ring and circumferential gap 19 of the seal ring are axially aligned. Accordingly, as shown in FIG. 2, the arrangement of the oil control ring and the seal ring substantially prevents formation of an axial oil path.
- oil scraped by oil control ring 15 and seal ring 16 is returned directly downwards or downwards from the inside of piston 13 through oil return paths 24.
- a part of the rest of the scraped oil enters into and stays in the interior of oil-ring groove 12 through the circumferential gap between abutted end portions of oil control ring 15.
- most of this oil in the interior of oil-ring groove 12 is also returned downwards through oil return paths 24.
- seal ring 16 substantially has no oil path in the radial direction and the abutment gap 22 at the abutted end portions of spring seal ring 17 is substantially zero, no oil path in the radial direction is formed from the interior of oil-ring groove 12 to the radially outer side through the seal ring and the spring seal ring. Therefore, the oil in the interior of oil-ring groove 12 can be prevented almost completely from escaping also in the radially outer direction.
- the zero circumferential gap between the abutted end portions of spring seal ring 17 is possible because of the radial clearance inside and outside of the ring.
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Pistons, Piston Rings, And Cylinders (AREA)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP1988045285U JPH01149549U (pt) | 1988-04-05 | 1988-04-05 | |
JP63-45285[U] | 1988-04-05 |
Related Parent Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US07330308 Continuation | 1989-03-29 |
Publications (1)
Publication Number | Publication Date |
---|---|
US5039116A true US5039116A (en) | 1991-08-13 |
Family
ID=12715042
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US07/520,118 Expired - Fee Related US5039116A (en) | 1988-04-05 | 1990-05-07 | Composite oil-ring |
Country Status (2)
Country | Link |
---|---|
US (1) | US5039116A (pt) |
JP (1) | JPH01149549U (pt) |
Cited By (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5603512A (en) * | 1995-02-15 | 1997-02-18 | Caterpillar Inc. | Side and gap sealed oil ring |
US20060060809A1 (en) * | 2002-12-20 | 2006-03-23 | Siemens Aktiengesellschaft | Valve |
US20070007481A1 (en) * | 2002-11-01 | 2007-01-11 | Siemens Aktiengesellschaft | Valve |
US20080229922A1 (en) * | 2007-03-23 | 2008-09-25 | Lahrman John C | Piston ring |
WO2013010518A3 (de) * | 2011-07-15 | 2013-07-25 | Fey Lamellenringe Gmbh & Co. Kg | Drosselklappeneinrichtung |
DE102016104853A1 (de) * | 2016-03-16 | 2017-09-21 | Federal-Mogul Burscheid Gmbh | Mehrteiliger Ölabstreif-Kolbenring mit verringerter Reibung |
US11085543B2 (en) * | 2019-01-30 | 2021-08-10 | Denso Corporation | Butterfly valve including a valve body, shaft, groove portion and seal ring |
US11713811B2 (en) * | 2018-07-17 | 2023-08-01 | Federal-Mogul Burscheid Gmbh | Multi-piece oil scraper ring with reduced friction |
Citations (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB190227811A (en) * | 1902-12-16 | 1903-10-08 | James Ashworth | Improvements in Packings for Hydraulic Rams, Pump Buckets, Pistons and the like. |
CH73952A (de) * | 1916-06-10 | 1916-12-16 | Rudolf Ferber | Verfahren zur Herstellung von gehämmerten Kolbenringen mit überlapptem Verschluß |
DE636202C (de) * | 1936-10-05 | Ernst Mahle Dipl Ing | Leichtmetallkolben fuer Brennkraftmaschinen | |
US2231801A (en) * | 1938-02-21 | 1941-02-11 | Cords William | Packing ring element and assembly |
US2321791A (en) * | 1940-03-19 | 1943-06-15 | Melville W Beardsley | Piston ring gas seal |
GB1004370A (en) * | 1963-07-27 | 1965-09-15 | Linde Eismasch Ag | Improvements relating to means for effecting a seal between two coaxial cylindrical surfaces |
US3362720A (en) * | 1965-07-01 | 1968-01-09 | Dresser Ind | Annular seal assembly |
US3370858A (en) * | 1965-08-23 | 1968-02-27 | Gould National Batteries Inc | Piston ring assembly |
US3400941A (en) * | 1967-05-24 | 1968-09-10 | Ford Motor Co | Piston ring assembly |
US3656770A (en) * | 1969-01-23 | 1972-04-18 | Daimler Benz Ag | Piston |
US4575107A (en) * | 1983-02-12 | 1986-03-11 | Kabushiki Kaisha Riken | Piston rings for internal combustion engine |
GB2164418A (en) * | 1984-09-10 | 1986-03-19 | Nippon Piston Ring Co Ltd | Piston-ring combination |
US4844487A (en) * | 1988-11-04 | 1989-07-04 | Kaydon Corporation | Lock-step duo step split sealing ring |
-
1988
- 1988-04-05 JP JP1988045285U patent/JPH01149549U/ja active Pending
-
1990
- 1990-05-07 US US07/520,118 patent/US5039116A/en not_active Expired - Fee Related
Patent Citations (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE636202C (de) * | 1936-10-05 | Ernst Mahle Dipl Ing | Leichtmetallkolben fuer Brennkraftmaschinen | |
GB190227811A (en) * | 1902-12-16 | 1903-10-08 | James Ashworth | Improvements in Packings for Hydraulic Rams, Pump Buckets, Pistons and the like. |
CH73952A (de) * | 1916-06-10 | 1916-12-16 | Rudolf Ferber | Verfahren zur Herstellung von gehämmerten Kolbenringen mit überlapptem Verschluß |
US2231801A (en) * | 1938-02-21 | 1941-02-11 | Cords William | Packing ring element and assembly |
US2321791A (en) * | 1940-03-19 | 1943-06-15 | Melville W Beardsley | Piston ring gas seal |
GB1004370A (en) * | 1963-07-27 | 1965-09-15 | Linde Eismasch Ag | Improvements relating to means for effecting a seal between two coaxial cylindrical surfaces |
US3362720A (en) * | 1965-07-01 | 1968-01-09 | Dresser Ind | Annular seal assembly |
US3370858A (en) * | 1965-08-23 | 1968-02-27 | Gould National Batteries Inc | Piston ring assembly |
US3400941A (en) * | 1967-05-24 | 1968-09-10 | Ford Motor Co | Piston ring assembly |
US3656770A (en) * | 1969-01-23 | 1972-04-18 | Daimler Benz Ag | Piston |
US4575107A (en) * | 1983-02-12 | 1986-03-11 | Kabushiki Kaisha Riken | Piston rings for internal combustion engine |
GB2164418A (en) * | 1984-09-10 | 1986-03-19 | Nippon Piston Ring Co Ltd | Piston-ring combination |
US4844487A (en) * | 1988-11-04 | 1989-07-04 | Kaydon Corporation | Lock-step duo step split sealing ring |
Cited By (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5603512A (en) * | 1995-02-15 | 1997-02-18 | Caterpillar Inc. | Side and gap sealed oil ring |
US20070007481A1 (en) * | 2002-11-01 | 2007-01-11 | Siemens Aktiengesellschaft | Valve |
US7237761B2 (en) * | 2002-11-01 | 2007-07-03 | Siemens Ag | Valve having double wound lamellar ring |
US20060060809A1 (en) * | 2002-12-20 | 2006-03-23 | Siemens Aktiengesellschaft | Valve |
US7159844B2 (en) | 2002-12-20 | 2007-01-09 | Siemens Ag | Two-part flap valve |
US7997185B2 (en) * | 2007-03-23 | 2011-08-16 | Mahle Engine Components Usa, Inc. | Piston ring |
US20080229922A1 (en) * | 2007-03-23 | 2008-09-25 | Lahrman John C | Piston ring |
WO2013010518A3 (de) * | 2011-07-15 | 2013-07-25 | Fey Lamellenringe Gmbh & Co. Kg | Drosselklappeneinrichtung |
DE102016104853A1 (de) * | 2016-03-16 | 2017-09-21 | Federal-Mogul Burscheid Gmbh | Mehrteiliger Ölabstreif-Kolbenring mit verringerter Reibung |
DE102016104853B4 (de) | 2016-03-16 | 2018-05-09 | Federal-Mogul Burscheid Gmbh | Mehrteiliger Ölabstreif-Kolbenring mit verringerter Reibung |
US20190113139A1 (en) * | 2016-03-16 | 2019-04-18 | Federal-Mogul Burscheid Gmbh | Multiple-piece oil stripping piston ring with reduced friction |
US11092238B2 (en) * | 2016-03-16 | 2021-08-17 | Federal-Mogul Burscheid Gmbh | Multiple-piece oil stripping piston ring with reduced friction |
US11713811B2 (en) * | 2018-07-17 | 2023-08-01 | Federal-Mogul Burscheid Gmbh | Multi-piece oil scraper ring with reduced friction |
US11085543B2 (en) * | 2019-01-30 | 2021-08-10 | Denso Corporation | Butterfly valve including a valve body, shaft, groove portion and seal ring |
Also Published As
Publication number | Publication date |
---|---|
JPH01149549U (pt) | 1989-10-17 |
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Legal Events
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FEPP | Fee payment procedure |
Free format text: PAYOR NUMBER ASSIGNED (ORIGINAL EVENT CODE: ASPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY |
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REMI | Maintenance fee reminder mailed | ||
LAPS | Lapse for failure to pay maintenance fees | ||
FP | Lapsed due to failure to pay maintenance fee |
Effective date: 19950816 |
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STCH | Information on status: patent discontinuation |
Free format text: PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362 |